This paper tries to analyze the mechanism of the evolution of family business based on the product market by constructing the simple model. The analysis indicates that the evolution of family business is the tactic conduct of owner obtaining the competitive dominance and that the entrance rampart of industry is an important parameter affecting organization evolution. The organization evolution in different industry is different because of the difference of the entrance rampart of industry. On the basis of the analysis, the authors consider the organization evolution based on industry support and then make basic conclusions.